THE EARTH. 25 



or by the driving of the froth along the shore ; or 

 by throwing out what is called the log-line, with 

 a buoy made for that purpose ; and by the direc- 

 tion and motion of this, they judge of the setting 

 and the rapidity of the current. 



These currents are generally found to be most 

 violent under the equator, where indeed all the 

 motions of the ocean are most perceivable. 

 Along the coasts of Guinea, if a -ship happens to 

 overshoot the mouth of any river it is bound to, 

 the current prevents its return ; so that it is 

 obliged to steer out to sea, and take a very large 

 compass, in order to correct the former mistake. 

 These set in a contrary direction to the general 

 motion of the sea westward ; and that so strong- 

 ly, that a passage which with the current is made 

 in two days, is with 'difficulty performed in six 

 weeks against it. However, they do not extend 

 above twenty leagues from the coast ; and ships 

 going to the East Indies take care not to come 

 within the sphere of their action. At Sumatra 

 the currents, which are extremely rapid, run 

 from south to north ; there are also strong cur- 

 rents between Madagascar and the Cape of Good 

 Hope. On the western coasts of America, the 

 current always runs from the south to the north, 

 where a south wind, continually blowing, most 

 probably occasions this phenomenon. But the 

 currents that are most remarkable are those 

 continually flowing into the Mediterranean Sea, 

 both from the ocean by the straits of Gibraltar, 

 and at its other extremity, from the Euxine Sea 

 by the Archipelago. This is one of the most ex- 



VOL. i. p 



